Ingredient review
PEG-45 Hydrogenated Castor Oil
INCI: PEG-45 Hydrogenated Castor Oil
A gentle, oil-based emulsifier that helps mix water and oil in formulas, but may feel heavy on very oily skin.
In plain English
PEG-45 Hydrogenated Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it water-soluble. It acts as a bridge between oil and water, allowing them to blend smoothly in creams, lotions, and cleansers. While it is generally well-tolerated and non-irritating, it can leave a slightly greasy feel on skin, especially for those with very oily or acne-prone skin.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
PEG-45 Hydrogenated Castor Oil is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging PEG-45 Hydrogenated Castor Oil.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A semi-synthetic ingredient made by reacting hydrogenated castor oil with ethylene oxide (PEG). The result is a waxy, water-dispersible emulsifier that helps stabilize oil-in-water emulsions.
How it works
It reduces the surface tension between oil and water, allowing them to mix into a stable, creamy emulsion. This helps products feel smooth and spread easily, while also helping to dissolve and remove oil-based impurities like makeup and sunscreen.
Pros
Gentle emulsifier
It helps create stable, creamy products that feel smooth and non-drying, making it suitable for sensitive skin.
Effective makeup remover
Its oil-loving nature helps dissolve stubborn makeup and sunscreen without requiring harsh rubbing.
Cons and cautions
May feel heavy
On very oily or acne-prone skin, it can leave a slight greasy film that some find uncomfortable.
PEG purity concerns
Low-quality PEG compounds may contain trace impurities; however, reputable cosmetic brands use purified, skin-safe grades.
Best for
- People with dry or normal skin who enjoy rich, creamy cleansers and lotions
- Those who wear heavy makeup or waterproof sunscreen and need a gentle oil-based remover
Use caution if
- Individuals with very oily or acne-prone skin who prefer lightweight, gel-based formulas
Usage tips
Safety summary
PEG-45 Hydrogenated Castor Oil is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential. The main safety concern is the potential for trace impurities in PEG manufacturing, but reputable suppliers and brands ensure high purity.
Research notes
The Cosmetic Ingredient Review (CIR) panel has evaluated PEG compounds and found them safe for use in cosmetics when formulated to minimize impurities. No significant skin sensitization or toxicity has been reported for this specific ingredient.
Common label clues
- Typical concentration
- 0.5% to 5% in leave-on products; up to 10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the US (FDA), EU (CosIng), and many other regions. The EU restricts PEG compounds to ensure low levels of impurities like ethylene oxide and 1,4-dioxane.
- Common uses
- Cleansers, Makeup removers, Creams, Lotions, Serums
- Environmental note
- PEG compounds are generally biodegradable, but their production involves ethylene oxide, which is derived from fossil fuels. Some brands now use bio-based PEG alternatives.
Good to know
- PEG-45 Hydrogenated Castor Oil is often used in combination with other emulsifiers to create a lighter feel.
- It is also used in some hair products to help condition and detangle.
Common questions
What is PEG-45 Hydrogenated Castor Oil in beauty products?
PEG-45 Hydrogenated Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it water-soluble. It acts as a bridge between oil and water, allowing them to blend smoothly in creams, lotions, and cleansers. While it is generally well-tolerated and non-irritating, it can leave a slightly greasy feel on skin, especially for those with very oily or acne-prone skin.
What does PEG-45 Hydrogenated Castor Oil do in a beauty product?
It reduces the surface tension between oil and water, allowing them to mix into a stable, creamy emulsion. This helps products feel smooth and spread easily, while also helping to dissolve and remove oil-based impurities like makeup and sunscreen.
Is PEG-45 Hydrogenated Castor Oil safe for most people?
PEG-45 Hydrogenated Castor Oil is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential. The main safety concern is the potential for trace impurities in PEG manufacturing, but reputable suppliers and brands ensure high purity.
Who should be careful with PEG-45 Hydrogenated Castor Oil?
Individuals with very oily or acne-prone skin who prefer lightweight, gel-based formulas
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.